One of the most remarkable courts martial in U.S. history begins tomorrow. Nidal Hasan goes on trial at Fort Hood in Texas. Back in 2009, Hasan, an Army psychiatrist, walked into the health clinic at that base and started shooting indiscriminately. He's charged with murdering 13 people and wounding more than 30 others.

BLOCK: The court martial will also be remarkable because Hasan is planning to represent himself.

NPR's Daniel Zwerdling has covered the story since the shootings and he joins us now. And, Danny, why don't you set the scene, what will this court martial be like?

DANIEL ZWERDLING, BYLINE: Nidal Hasan will be wheeled into the courtroom in a wheelchair because during the shooting rampage military policeman shot him and he's paralyzed from the waist down. He'll have a big bushy beard. There was a huge controversy over whether he could wear one at the trial. And he will be the man acting as his own lawyer, asking questions of the victims who he shot. And I say who he shot because he has taken credit for the shooting.

He tried to plead guilty and the military tribunal would not allow him; because under military statute, if you can potentially be executed for a crime, you can't plead guilty. So this is not going to be a court martial about did Nidal Hasan shoot those people or not. This is really a court martial about will he be sentenced to death or not.

BLOCK: And, Danny, listeners may remember that soon after the shooting, you - along with other reporters - revealed that officials in both the Army and the FBI had been worrying about Nidal Hasan in the months and years leading up to this shooting. And those worries were not acted on.

ZWERDLING: For years, Hasan trained and worked as a psychiatrist at Walter Reed here in Washington, D.C. for six years. And from the beginning, his supervisors said he was a bad psychiatrist - he was unprofessional. One of them tried to get rid of him. In the year leading up to Fort Hood, some of his supervisors actually sat around in meetings and discussed: Could Nidal Hasan be psychotic. And one even wondered aloud to colleagues, according to the sources I've talked to, do you think Nidal Hasan could commit fratricide. And, of course, that's when a soldier shoots a fellow soldier.

But they decided in the end, you know, it would be really valuable to have a Muslim psychiatrist in the Army, if we could just set him on the right path. And number two, some of the supervisors were worried, if we try to get rid of him, it could be a long, messy legal battle.

Meanwhile, at the FBI in the year leading up to Fort Hood, they were spying on the radical cleric Anwar al-Awlaki. And lo and behold, this Army psychiatrist, Nidal Hasan is starting this email exchange with al-Awlaki. And some of the FBI agents thought, you know, this guy is potentially dangerous. But there was a big debate about the emails and what they meant. And the FBI eventually ruled, no, he's just doing research for a graduate degree at the military's university.

BLOCK: Well, Nidal Hasan is facing the prospect potentially of being sentenced to death. What kind of precedent is there for this kind of case?

ZWERDLING: Now, in 2003, you might remember a soldier - a Muslim American soldier - in Kuwait threw hand grenades into tents as soldiers were sleeping and then opened fire with his rifle on them. He killed two, injured more than a dozen. He was sentenced to death in a court martial. But for Nidal Hasan, having killed so many, wounded so many and representing himself, the experts I've talked to say they can't think of anything else like it in military judicial history.

BLOCK: And how long is the court martial of Nidal Hasan expected to last?

ZWERDLING: There is a lot of witnesses. They expect it to take six to 12 weeks.